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<b>thus </b><a NAME="E1:8_1_1"/>
the <a href="msualg_1.html#U4">Sorts</a> of <span class="p1"><a href="pralg_2.html#K9">[:</a><span class="default"><font color="Maroon">c<sub>2</sub></font>,<font color="Maroon">c<sub>3</sub></font></span><a href="pralg_2.html#K9">:]</a></span> is <a href="relat_1.html#V2">non-empty</a>
  <i><font color="Red">:: according to </font></i><a class="ref" href="msualg_1.html#D8">MSUALG_1:def 8</a><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="8_1_1_1"><b>proof </b></a><div class="add">

<a NAME="E1:8_1_1_1"/>
<span class="p1"><a href="pralg_2.html#K9">[:</a><span class="default"><font color="Maroon">c<sub>2</sub></font>,<font color="Maroon">c<sub>3</sub></font></span><a href="pralg_2.html#K9">:]</a></span> <a href="hidden.html#R1">=</a>  <a href="msualg_1.html#G3">MSAlgebra</a>(# <span class="p1"><a href="pboole.html#K10">[|</a><span class="default">the <a href="msualg_1.html#U4">Sorts</a> of <font color="Maroon">c<sub>2</sub></font>,the <a href="msualg_1.html#U4">Sorts</a> of <font color="Maroon">c<sub>3</sub></font></span><a href="pboole.html#K10">|]</a></span>,<span class="p1"><a href="pralg_2.html#K5">[[:</a><span class="default">the <a href="msualg_1.html#U5">Charact</a> of <font color="Maroon">c<sub>2</sub></font>,the <a href="msualg_1.html#U5">Charact</a> of <font color="Maroon">c<sub>3</sub></font></span><a href="pralg_2.html#K5">:]]</a></span> #)
 
<b>by </b><i><a class="ref" href="pralg_2.html#D15">PRALG_2:def 15</a></i>;<br/>
<b>hence </b><a NAME="E2:8_1_1_1"/>
the <a href="msualg_1.html#U4">Sorts</a> of <span class="p1"><a href="pralg_2.html#K9">[:</a><span class="default"><font color="Maroon">c<sub>2</sub></font>,<font color="Maroon">c<sub>3</sub></font></span><a href="pralg_2.html#K9">:]</a></span> is <a href="relat_1.html#V2">non-empty</a>
 ;<br/>


</div><b>end;</b></div>


</div>
